Receptor model anionic

Derivatives in the s- and p-Block Elements Supported by Poly(pyrazolyl)borato Ligation Models for Carbonic Anhydrase, Receptors for Anions, and the Study of Controlled Crystallographic Disorder Gerard Parkin... 

ALKYL, HYDRIDE, AND HYDROXIDE DERIVATIVES OF THE s- AND p-BLOCK ELEMENTS SUPPORTED BY POLY(PYRAZOLYL)BORATO LIGATION MODELS FOR CARBONIC ANHYDRASE, RECEPTORS FOR ANIONS, AND THE STUDY OF CONTROLLED CRYSTALLOGRAPHIC DISORDER... 

Seel, C., Galan, A., de Mendoza, J. Molecular Recognition of Organic Acids and Anions -Receptor Models for Carboxylates, Amino Acids, and Nucleotides. 175, 101-132 (1995). 

To come to a water-soluble, ditopic receptor model, Lehn etal. attached JV6-[24] crown-8 with an acridine-derived DNA-intercalator, so combining the anion binding strength of the first (in protonated state) [67] with the n-stacking capacity of the latter. Indeed, increased binding of ATP by 46 was observed as compared with the unsubstituted azacrown [68]. Additionally, the multifunctional host 46 catalyzes the hydrolysis of ATP [69] with a higher selectivity over ADP as compared with the parent crown but with a somewhat reduced eflectiv-ity. The reaction intermediate was shown to be the Af-phosphorylated crown. 

Molecular Recognition of Organic Acids and Anions -Receptor Models for Carboxylates, Amino Acids, and Nucleotides... 

Figure I. Schematic structures of model anionic receptor sites, ammonium methylphosphate (AMP), ammonium methylsulphate (AMS), and the eight compounds studied...

The object of this initial study was to determine whether any net interactions could occur between typical N-substituents and the model anionic receptor site involved in H-bonding with the protonat d amine group, without the steric constraint of attachment of the substituent to the nitrogen. 

N-SUBSTITUENTS WITH MODEL ANIONIC RECEPTOR SITES ... 

Figures 2 and 3 show the optimized geometries obtained from both the PCILO and empirical energy methods for complexes of AMP and AMS with five of the eight compounds studied. The PCILO results give distinct n-ir complexes involving interaction of one oxygen lone pair of electrons with the ir-electron system of the substitutent. In all cases, the empirical energy method gives a totally optimized complex which involves mainly electrostatic and dispersion terms. As can be seen from Figures 2 and 3, the interaction of methylcyclopropane with the model anionic receptor site is the one with the greatest difference...

TABLE III. ANTAGONIST POTENCY AND BINDING AFFINITY OF BENZOMORPHANS WITH VARYING N-SUBSTITUENTS AND THEIR ENERGIES OF INTERACTION WITH MODEL ANIONIC RECEPTOR SITES. ... 

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